The former Manchester United and Ireland captain would have played with Cristiano Ronaldo towards the end of his playing days with the Red Devils and he was always a fan of the Portuguese star.

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“I liked the lad straightaway. He had a nice presence about him, and a good attitude,” Keane writes in The Second Half, his second autobiography.

“What impressed me most was that he’d been given the option of staying in Lisbon for another year, on loan, but he said no; he’d come over to Manchester straightaway. I thought it was a good, brave decision – because he was only seventeen.

“After the first few days, watching him train, my reaction was, ‘This lad is going to be one of the world’s greatest players.’ I didn’t say it publicly, because I’d always be wary of building a player up too early – or knocking him down.”

“He was very likeable.”

“He looked like a player. You have to look the part, and he did. Zidane looked like a player – and Ronaldo looked like a player.

“The shape, the body language – they were there. A bit of arrogance, too. But he’d a nice way about him; he was very likeable.

“We forget that he was very heavily criticised when he first came on the scene. He was going down too quickly when tackled, his final product wasn’t good enough.

“But – again – he was only seventeen, a kid. I was playing youth football for Rockmount, in Cork, at that age.

“He was amazing. He was immediately one of the hardest-working players at United.

“Most of the players I knew worked hard, but Ronaldo had the talent on top of the work rate.”

“I always felt that football was his love.”

“He was good-looking and he knew it,” Keane said.

“He was vain in that sense. At the mirror. He was a big lad, a big unit. I’d think, ‘Good on yeh.’ Looking at some of the other lads in front of the mirror, I’d think, ‘Yeh fuckin’ nugget.’ But Ronaldo had an innocence to him and a niceness.

“I don’t think he ever slackened off, or that he was ever more worried about the mirror than his game. I always felt that football was his love.”